Regulator



Jan. 31, 1961 R. D. CUMMINS 2,969,801

REGULATOR Filed Jan. 17, 1958 T v INVENTOR.

REGULATOR Richard D. Cummins, Tonawanda, N.Y., assignor to FirewelDevelopment Company, Buffalo, N.Y., a copartnership Filed Jan. 17, 1958,Ser. No. 709,683

2 Claims. (Cl. 137-64) This invention relates to a regulator, and moreparticularly to a regulator for use in maintaining a minimum referencepressure in oxygen breathing or suit pressure apparatus.

In my copending application Serial No. 669,365, filed July 1, 1957,there is disclosed an aneroid valve for maintaining a minimum referencepressure for oxygen breathing apparatus or pressure suits, at altitudesabove 35,000 feet, and which valve, upon rupture of the bellows, willprevent a build up of excessive and/or harmful pressures in such oxygenbreathing apparatus or pressure suits. The present invention operates ina similar manner, however, it features a compound arrangement of aneroidvalves providing a compact and efiicient device for such pressurecontrol purposes. More particularly, it effects space saving economiesby a reduction in size, and in addition, reduces the number of hoseconnections required.

A general object of the invention is to provide a regulator havinganeroid valves which will maintain a minimum reference pressure foroxygen breathing apparatus or pressure suits at altitudes above 35,000feet, and which will prevent a build up of excessive and/ or harmfulpressures in event of rupture of an aneroid valve.

A further and more specific object is to provide such a regulator whichfeatures a compound arrangement of aneroid valves providing a compactassembly which affords space saving economies, and which reduces thenumber of hose connections when both the pressures of oxygen breathingapparatus and the pressure suit is to be regulated.

These and further objects and features of the invention will become moreapparent from the following description and accompanying drawingwherein:

Fig. 1 is a section view through a representative embodiment of theinvention;

Fig. 2 is an enlarged section view of an aneroid valve used in the'device of Fig. 1; and

Fig. 3 is an enlarged section view of a restricting orifice used in thedevice of Fig. 1.

Referring now to the drawing, the numeral 6 identifies a regulatorembodying the principles of the invention, which includes a body portion7 having a pair of oppositely disposed threaded recesses 8, 9, and apair of oppositely disposed openings 11, 12. The recesses 8 and 9 areadapted to receive aneroid valve arrangements 13, 14, each of whichcomprise a threaded cap 15, a headed pin member 16 which is secured tothe inside of the cap by a screw 17, an evacuated bellows 18 one endbeing supported by the pin member 16 the other end having an axiallypositioned valve button or facing, this button or facing for the aneroidvalve 13 being designated at 19 and for the aneroid valve 14 at 19a, anda spring 35 compressively arranged between the inside of one end of thebellows 18 and the head of the pin member 16. An opening 20 is formed inthe cap to expose the exterior of the bellows 18 to atmospheric pressureat all times. The only difference between aneroid valve 14, as comparedwith aneroid valve 13, is that the button or facing atent O 2,969,801 C6Patented .Jan. 31, 1961 19 of the latter is of less diameter than theequivalent button 19a of the former, as seen in Fig. 1, the reason forwhich will be explained. It will be seen that the free end of thebellows 18 is spaced a certain distance from the end of the pin member16, to limit the axial movement of the bellows under maximum pressuredifferential.

A first pressurized oxygen supply passageway 21 is arranged in the bodyportion 7 and extends upwardly where it is bifurcated for connectionwith each of the openings 11 and 12. The passageway 21 is threaded forreceipt of a hose or conduit 22, which leads to an oxygen supply fordelivery of oxygen at approximately 70 p.s.i. to the regulator 6.Extending from the passageway 21 are passageways 23 which are arrangedto connect the passageway 21 with each of the threaded recesses 8 and 9,said passageways 23 having a pair of metering orifice plugs 24 disposedtherein. As best seen in Fig. 3, each orifice piece 24 includes a filter26 adapted to strain the oxygen which will flow in passageway 23.

The end of passageway 23 opening into recess 9, has a valve seat 25,while the end of the passageway 23 opening into recess 8 has a valveseat 30. The valve seats 25 and 30 each are of a diameter whichcorresponds with the diameter of the adjacent facing 19 and 19arespectively of bellows 18.

The openings 11 and 12 each form a first demand valve chamber arrangedfor communication at certain times with the passageway 21. An outletline 27 can lead from the chamber 11 to the mechanism controlling thepressure in a crewmans face mask (not shown), while an outlet line 28can lead from the chamber 12 to a crewmans pressure suit (not shown).Each demand chamber 11 and 12 has a flexible diaphragm 29 the edges ofwhich are clamped against the rim of the chamber by a cap 31. Eachdiaphragm 29 therefore forms a pair of chambers at its opposite sides,the inside chambers being designated at 11 and 12 respectively, and theoutside chambers being designated at 11a and 12a respectively. A pair ofpassageways 32 connect each end of passageway 23 with the correspondingchamber 11a, 12a between each diaphragm 29 and the cap 31, as best seenin Fig. 1. A light spiral compression spring 33 is arranged between eachcap 31 and diaphragm 29 to bias the diaphragm toward the respectivechamber 11 or 12. Each diaphragm has a metal disc 34 adapted to engage aknob 36 located on the end of a valve stem 37. Each valve stem 37extends through a central aperture 38 of a metal disc 39 located in abore 41 formed in the bifurcated passageway 21, and has a cap shapedvalve head 42 which seats against the high pressure side of the disc 39.A spiral compression spring '43 holds the stem 37 normal to the disc 39so that the valve head "42 is seated against the disc aperture 38, thuspreventing flow of high pressure oxygen from the passageway 21 intodemand chambers 11 and 12,

In the operation of the regulator 6, it will be assumed that oxygenunder a gage pressure of say 70 p.s.i. is being supplied to the conduit22. At altitudes below about 35,000 feet the demand valves i.e., thevolume between a diaphragm and cap 31, are referred to ambient pressureby reason of the fact that each passageway 32 is in communication with arecess 8 or 9 since the bellows facings 19 and 19a will be held fromengagement with a respective valve seat 25 or 30 due to the pressuredifferential to which each bellows is subjected. During this time asmall amount of oxygen, say, 20 cubic centimeters per minute, isconstantly being bled through each orifice piece 2 4 into the recesses 8and 9, and escapes to atmosphere via cap hole 20.

As the airplane rises in altitude the ambient pressure within therecesses 8 and 9 decreases causing the evacuated bellows 18 to expandaxially. When the ambient pressure drops to a critical value of 3.4p.s.i.a., the bellows expand sufliciently to seat the valve buttons 19,19a against the valve seats 25 and 30*, to thereby isolate the demandvalves from communication with the atmosphere. The oxygen bleeding pastthe orifice pieces 24 in passageway 23, builds up the pressure on thepassageways 32, and in the chambers 11b, 12b between each diaphragm 29and cup 31, to supply a higher than ambient reference pressure to thedemand valves.

The eifective area of the button or valve facing 19a of the aneroidvalve 14 is approximately five times greater than the eiiective area ofthe valve facing 19 of aneroid valve 13. The bellows valve facings 19,19a are so proportioned so that it will take a pressure of approximately17 p.s.i.a. to unseat the valve button 19 of bellows 13, while apressure slightly above 3.4 p.s.i.a. is all that is required to unseatthe valve button 19a of the bellows 14. Hence, the reference pressuremaintained in the demand valve for service of the crewmans mask i.e., inthe volume between the diaphragm and cap, will he just onedifth thevalue of the reference pressure maintained in the demand valve forservice of the orewmans pressure suit.

In the event of failure of either bellows, as by rupture, it will beseen that the spring 35 will force the corresponding valve facing 19,19a into engagement with a respective valve seat. This will allow abuild up of pressure against the valve facing by reason of the oxygenflowing through an orifice piece 24, and when such pressure reaches apredetermined maximum, the valve facing will be unseated to allow escapeof oxygen to atmosphere via hole 20. In such manner, the danger ofexcessive build up of suit or mask pressure from this cause, will beavoided. While a safety relief valve could be arranged to prevent suchbuild up pressures, such a relief valve would increase the danger ofleakage, hence, is not desirable. 4

From the foregoing it will be seen that the regulator of the inventionprovides a compact and effective device for the regulation of pressuresin a face mask and pressure suit, and that other objectives of theinvention are satisfied.

The foregoing description has been given in detail without thought oflimitation since the inventive principles involved are capable ofassuming other physical embodimerits without departing from the spiritof the invention and the scope of the appended claims.

What is claimed is:

l. A regulator comprising a body portion formed to provide a first inletpassageway for the supply of pressurized oxygen to the regulator, a pairof demand valves each having a first chamber connected to an outlet anda second chamber, a diaphragm separating each of said first and secondchambers and each said demand valve in said first chambers beingresponsive to movement of its respective diaphragm for providingcommunication between each said first chamber and said first pressurizedoxygen supply passageway, said body portion being formed to provide apair of recesses each of which is open to atmospheric pressure and is incommunication with said first pressurized oxygen supply passageway via asecond passageway, an evacuated bellows arranged within each recess andresponsive to a given atmospheric pressure therein, means attaching oneend of each of said bellows to said body portion, each of said bellowshaving a facing at its other end for engaging an outwardly facing seatupon the end of the corresponding second passageway, and resilient meanswithin said bellows biasing said facing against said seat to disrupt thecommunication between the recess and the corresponding secondpassageway, said body portion also being formed to provide a thirdpassageway providing communication between each second passageway andeach said second chamber of each demand valve.

2. A regulator according to claim 1, wherein the efiective area of thefacing and seat of one bellows is greater than the effective area of thefacing and seat of the other bellows.

References Cited in the file of this patent UNITED STATES PATENTS2,437,462 Frye Mar. 9, 1948 2,449,548 Burns Sept. 21, 1948 2,703,572Seeler Mar. 8, 1955 2,755,799 Marty July 24, 1956 2,824,557 Mejean eta1. Feb. 25, 1958 2,834,343 Keckler et al. May 13, 1958

